Everything You Need to Know about Narcissists, Psychopaths, and Abuse - click on this link: http://www.narcissistic-abuse.com/faq1.html
According to Freud and his followers, our psyche is a battlefield between instinctual urges and drives (the id), the constraints imposed by reality on the gratification of these impulses (the ego), and the norms of society (the superego). This constant infighting generates what Freud called "neurotic anxiety" (fear of losing control) and "moral anxiety" (guilt and shame).
But these are not the only types of anxiety. "Reality anxiety" is the fear of genuine threats and it combines with the other two to yield a morbid and surrealistic inner landscape.
These multiple, recurrent, "mini-panics" are potentially intolerable, overwhelming, and destructive. Hence the need to defend against them. There are dozens of defense mechanisms.
(From the book "Malignant Self-love: Narcissism Revisited" by Sam Vaknin - Click on this link to purchase the print book, or 16 e-books, or 3 DVDs with 16 hours of video lectures on narcissists, psychopaths, and abuse in relationships: http://www.narcissistic-abuse.com/thebook.html)